a) Field of the Invention
The present invention relates to a paper shredder blade, and more particularly to a differential blade of a paper shredder blade tool, wherein a plurality of bumps are provided on the differential blade to increase a thickness of a secondary blade and to enhance an intensity of the blade, and two secondary blades are formed into a set of differential blade by abutting the bumps with the bumps, so as to save materials. In addition, a reinforcing rib is provided on a cut-off edge of the secondary blade; therefore, a blade edge will be thicker, such that when cutting off paper at a same time, the paper can be cut off easily by the secondary blades without being prone to be jammed.
b) Description of the Prior Art
Referring to FIG. 1, a conventional paper shredder blade tool is constituted by two cylindrical hobs 1, 1′. Each hob includes a polygonal shaft 2 and a plurality of differential blades 4 sheathed on the shaft 2, and a gasket 6 is provided between two neighboring differential blades 4 to separate the blades 4, allowing the differential blades 4 on the two cylindrical hobs to be assembled alternately. Referring to FIG. 2, each differential blade 4 is formed by two sets of secondary blades 4a abutted back to back, and a circumference of each secondary blade 4a is provided with a plurality of cut-off edges 4b. When the cut-off edges 4b of the paper shredder are cutting off paper, the paper will be cut off at a same time by the cut-off edges 4b. A single sheet of paper is easily cut off, whereas when cutting off the plural sheets of paper, a larger output horsepower will be needed, a louder noise will be created and a force sustained by a driving gear of the paper shredder will be relatively larger, such that teeth on the gear can be broken.